Doubts During the Sa´ī
Doubts concerning the number or validity of segments are of no relevance if they arise when the pilgrim is already engaged in the next ritual, e.g. after the taqsīr, in case of an ´Umrah, or when performing ṯawāf-un-nisā, in case of the Hajj. If the doubts arise directly after the sa´ī and they concern redundantly added distances, they have to be ignored, but if they are related to omissions, they cause the sa´ī to become invalid.
#348: If the pilgrim arrives in Marwa after the last segment and they are uncertain as to whether it was the seventh or the ninth segment, this doubt should be ignored and the sa´ī is valid. If the doubt arises when the pilgrim is still on their way, the sa´ī is rendered invalid and they have to perform it once again.
#349: The ruling in the case of doubt concerning the number of segments during the sa´ī is the same as for doubt about the number of rounds in the course of the ṯawāf. Which means that it causes the sa´ī to be invalidated.